ANTIBODY-RESPONSES TO BRUCELLA-ABORTUS-2308 IN CATTLE VACCINATED WITHBRUCELLA-ABORTUS RB51

Cattle vaccinated with Brucella abortus rough strain RB51 (SRB51) prod uced small amounts of serum immunoglobulin G (IgG) but no IgM antibody to smooth strain 2308 (S2308) bacteria and produced no IgG or IgM ant ibody to S2308 lipopolysaccharide (LPS). Western immunoblot analysis r evealed that antiserum from SRB51-vaccinated tattle contained IgG anti body that reacted with S2308 proteins of 84 to <20 kDA. However, antis erum from the vaccinated cattle did not contain agglutinating B. abort us antibody in the tube agglutination test for brucellosis. These resu lts suggest that SRB51-vaccinated cattle produced no antibody to S2308 LPS, although they did produce nonagglutinating IgG antibody that rea cted with S2308 bacteria and bacterial proteins of 84 to <20 kDA.